dave@zinfandel.UUCP (09/29/84)
I am interested in getting a mouse for my C64. Using a mouse for hires graphics
work would be much more preferable than using a joystick.
I know Radio Shack has a mouse for their color computer for $49.95 (on sale
for $34.95). It has a DIN type connector. Could it be so easy as to cut
off the DIN connector and wire up the sub-D connector? Radio Shack's
joysticks use two pots for x/y direction and a separate switch for the 'fire'
button. According to the C64 Reference Manual, the Commodore joysticks
use 'digital switches'.
Does anybody out there know how the joysticks really work? Other than the
connector, are Radio Shack's controllers compatible?
Dave Funk
Zehntel, Inc.
2625 Shadelands Drive
Walnut Creek, CA 92598
(415) 932-6900 x309
....!decvax!sytek!zehntel!dave
...."zehntel!dave"@BERKELEYcalway@ecsvax.UUCP (10/04/84)
x
Most mechanical "mice" are similar to the digital joystick used by Commodore,
but I don't know about the Radio Shack mouse.
An alternative you might consider is the trackball. A trackball is simply a mouse upside down. Wico makes one for the Commodore computer. Costs about $50.
It's a bit bulky but still takes up less desk space than you would need for
most mice.
James Calloway
The News and Observer
Box 191
Raleigh, N.C. 27602
(919) 829-4570
{akgua,decvax}!mcnc!ecsvax!calwaydunkelbe@ecn-ee.UUCP (10/04/84)
<you want me to do what???> The C64 has two pot inputs on the video chip which are most consistantly read by syncing with the video. In other words, always check the raster register and read on the same line of video to prevent jitter on the value read back from the analog inputs. If the RS mouse is like any of the others I have seen, it will be sending pulses down the switch oriented joystick lines just as if the user was repeatedly moving the joystick one of the four directions and letting it come back to center. I would be surprised if the mouse had any type of pot action since all software would have to take into account the wrap-around for every rotation of the wheel. The programmer's reference manual has all the info you need. For the pot interface, refer to the VIC chip description section. The joysticks are connected to a parallel port which normally runs the keyboard. With a little bit of machine language programming, you could get a neat little interrupt driven mouse routine for $40. Kirk Dunkelberger pur-ee